Influence of sodium chloride on the cloud point of polyethoxylate surfactants and estimation of Flory-Huggins model parameters
Journal Title: Revista Facultad de Ingeniería-Universidad de Antioquia - Year 2015, Vol 1, Issue 75
Abstract
In this study, the influence of NaCl on the cloud point of polyethoxylate surfactants from the family of lauryl alcohol polyethoxylates (C12EOn) and nonylphenol polyethoxylates (NPEOn) was investigated. Liquid-liquid equilibrium curves of the aforementioned aqueous surfactants system with the presence of NaCl were plotted and thermodynamic parameters based on the Flory Huggins model were obtained. The visual method was used to determine the cloud point. Solutions containing surfactant concentrations between 0.5 and 20% (by weight) and NaCl between 4.9 and 12.1% (by weight) were prepared. Salt had a salting-out effect, decreasing surfactant solubility in water. Furthermore, the cloud point decreased with an increase of NaCl concentration. The Flory-Huggins model satisfactorily described the experimental data for all surfactant + NaCl aqueous mixtures studied.
Authors and Affiliations
Alessandro Alisson de Lemos Araújo, Eduardo Lins de Barros Neto, Osvaldo Chiavone-Filho, Edson Luiz Foletto
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